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Bob Harper

Bob Harper

Joined on December 20, 2004

Last Post on May 2, 2013

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before OSHA vs with it

@ July 26, 2012 8:15 PM in Tidbit #5: a guessing game

Growing up in the family business building homes, I saw and committed practices that today would get you a hefty fine from OSHA. We didn't have a lot of workplace injuries but there have been enough around the country to warranty many, if not most of the regs. the CFR. I hate the notion of all these overboard OSHA regs. but being involved with the safety of an entire $.5 billion company sitting in on weekly conference and NetGoto-type meetings, I do see where these things go wrong and often with tragic consequences. It's not just how many guys got a boo-boo or went to the ER but how many went home that night. The 10 Hr course was an eye-opener for one of those know-it-alls who took the course because he should/had to. Now, I recommend it to everyone involved in construction and service industries. Note that the 10 hr. course is just a primer--it does not make you a safety authority. It should whet your appetite to learn more and here's the key: frequently and consistently. You must have a safety plan, work the plan, evaluate the plan and revise it frequently or as driven by incidents.
As for confined spaces, basements, and working in dungeons, rooftops, suspended ceilings, etc.: We know a LOT more than we did when I was a kid. So why do we ASSume those practices of the '60s are still adequate today? First of all, technology and construction is constantly leading to new and more efficient ways to hurt and kill the unwary. But I mean, how responsible are we to send employees out into these areas without a 4 in 1 personal gas alarm? Your required daily service truck walk-around inspection for DOT includes sounding the horn. Is that more important that the air you breathe or work in? Ask yourself of all the hazards you encounter in a routine workday, which are the most likely to kill or maim, then write a plan to address that hazard with avoidance, mitigation and PPE followed by what is your response if things do go wrong. By that, how do you propose for a rescuer (to be named by you) to ascertain if it is safe enough to enter where the fallen is, make an assessment, and extricate him if he is not entangled or requires spinal precautions. If not, do you have 911 service where you work? It wasn't working in the Adirondacks where I was last weekend and no landlines. How far is your local EMS and are they basic only or do they have advanced life support (paramedics)? BTW, I'm a retired paramedic/ firefighter and I've been in more places I now know I had no business being in such as hazardous vapor clouds, downhill slippery slopes, drowning/ suffocation hazards, Haz-Mat spills, crazy armed people, etc.
OSHA regs are MINIMUM stds. You can exceeed them. If your hazard assessment indicates increased preparation, planning, protection, PPE, support personell and equipment, then do it. Back when I first got into chimney sweeping on my days off, my mentor was jumping from rooftops up onto chimneys just to install a lousy cap. I asked him and myself was my life worth the price of that cheap cap? Now, I use a LOT of ladders and adjuncts or I don't go. I'll leave Spiderman to the comics. BTW, my low level CO monitor alerts everyday in traffic--think about it.

crawlspace safety

@ July 24, 2012 10:44 PM in Tidbit #5: a guessing game

What if there had been CO, LPG within the flammability limits, or hot electrical where you would be electrocuted?
We should not be entering these spaces without a personal CO/ LEL/ O2/H2S alarm and a PASS such as firefighters wear. You described what OSHA would consider as a 'confined space' which warrants a written safety plan, pull a permit, and special gear, not to mention a helper. We must be nuts to enter these spaces routinely.

CSST

@ July 16, 2012 7:45 PM in Replacing Propane Cu Piping

Mark, I hold you in the higest regard as does the industry and I respect what you have said and don't disagree. I did not mean to come across as flippant but merely to counter a little of the hysteria I see over CSST. Sure, there have been and will continue to be failures. Yes, there are newer versions claiming to be more 'resistant' than the first generation. Sure, there are testing labs and listing stds. However, inspite of all that engineering we still cannot replicate certain types of lightning phenomena. We still don't know enough to predictably replicate it in the lab through various iterations of potentials and bonding.
I have seen copper tube fail and not just from lightning. When you have a structure fire from any ignition source, it tends to kink then fail and discharge with a similar result as a CSST lightning incident. Sch40 steel softens under fire load then fails at threads. A lot of it comes down to the question of would the house have been lost due to the lightning strike whether gas was supplied  or not and if so, would the gas piping really make that much difference? In some cases, it sure would while in other cases not necessarily.
My other point is to compare the CSST-related losses to non-CSST related ones to see the statistical correlation. If we want to save lives and protect people from our homes killing us, I can give us a few places to look starting with combustion venting WRT carbon monoxide and unfriendly fires. Keep up the good work Mark!

engineering vs lightning?

@ July 16, 2012 2:14 PM in Replacing Propane Cu Piping

The forces involved in lightning strikes cannot be reliably measured or replicated based upon varying conditions to produce a reasonable degree of repeatability and thus reliability. Therefore, we are left to base decisions primarily upon anecdotal evidence and opions. Given the current state of alarmism in the country, it is more stylish to make a big public spectacle over the 'epidemic' problem of lightning vs. CSST. Meanwhile, more people get killed by bath tubs than lightning striking homes but where's the public outcry against those evil tubs? We do not have an obligation, moral or otherwise, to design and construct against any possible threat conceivable by Gene Roddenberry or to the ANSI Std for Superman's cape. We have an obligation to design and build to what are the conditions of use that can reasonably be expected. It is reasonable to expect a few homes to suffer a major house fire but is it reasonable to require fire sprinklers, with all their complications, for every residential unit? That debate rages on but the hysteria surrounding the evils of CSST just grows. Meanwhile, the copper tubing, iron pipe and polymeric tubing guys are sitting by very quiet hoping not to get noticed. A NASA scientist who worked on the issue of lightning vs spacecraft noted the better bonded, the higher the probability for a lightning strike. The panic over CSST and lightning has us improving the bonding of these systems with no reliable way to replicate to a reasonable degree of engineering certainty the anticipated conditions of use or probability of a hit or measure the strike potential. Personally, I'm more worried about the laceration hazard from rocks thrown by lawn mowers through the proposed all glass houses of the future....

gas piping flare vs compression fittings code reference

@ July 10, 2012 8:35 PM in Replacing Propane Cu Piping

http://www.tracpipe.com/Customer-Content/WWW/Literature/FactSht.pdf

2009 IRC G2414.10.2 (403.10.2) Tubing joints. Tubing joints shall be made with approved gas tubing fittings or be brazed with a material having a melthing point ub excess of 1,000F (538C) or made with press-connect fittings complying with ANSI LC-4 Brazing alloys shall not contain more than 0.05-percent phosphorous.
G2414.10.3 Flared joints. Flared joints shall be used only in systems constructed from nonferrous pipe and tubing where experience or tests have demonstrated that the joint is suitable for the conditions and wehre provisions are made in the design to prevent separation of the joints.
Your AHJ can approve or disapproved fittings but he *should* rely on testing reports from an approved testing lab or service.

HTH

venting per mfr

@ July 6, 2012 4:05 PM in venting in a retrofit situation

According to the information presented, you must maintain the same diameter of the vent connector all the way to the chimney and only there can it be downsized one size. The mfr. requires this connector be 'insulated' yet this goes against NFPA 211 with one exception--listed connector. You can use a type 'B' or 'L' vent connector and meet this requirement legally. This will tend to reduce condensation, reduce clearances to combustibles yet meet NFPA 211, the listed instructions and the code. You can NOT wrap insulation over unlisted single walled or listed connector regardless of what a mfr says. This hides the connector from inspection which leads to failures going undetected. Wrapping a listed connector voids the warranty and listing as it invades the stated clearance to combustibles. Clearances are air spaces. Sure sure to support this connector, too. Use a 'draft hood connector' where it joins with the appliance flue collar. Seal it with a sealant rated for this duty rating, which should be in excess of 600F, which takes red RTV out of it. For a high temp. seal that is removeable unlike most furnace cements, try Mil-Pac refractory sealant. It is used a lot in the hearth industry and works great.

venting

@ July 2, 2012 1:19 PM in venting in a retrofit situation

The mfr requires you inspect the B-vent and replace it if ANY deterioration is present as they deem deterioration an unsafe condition. The specify inspect it inside and out. That means an NFPA 211, Ch 14. level II inspection. When you look at B-vent warranties, you will quickly realize an appliance rated at 83.7%AFUE will rot this vent much quicker than a low efficiency typical CAT I B-vented appliance. Now, the mfr also states this appliance cannot EVER be under negative pressure. That means you would have to install a powered makeup air system interlocked to the gas control in order to meet this requirement. Failure to do so with such a higher efficiency CAT I appliance will likely result in flue gas spillage and backdrafting regardless of vent sizing or materials. The section of code Timmie quoted allows vent downsizing on a restricted basis. One of those restrictions is that fan assited appliances cannot be downsized. Not sure how this unit was listed without a fan assist at that AFUE but that doesn't make it a good idea to sell or install. The code also requires the venting work. The only way to determine this is testing. It is not enough to verify it meets the written requirements by the code and mfrs listed instructions.

copper tubing for gas

@ July 2, 2012 12:51 PM in Replacing Propane Cu Piping

Copper tubing is allowed if the gas contains less than 0.3 grains of hydrogen sulphide per 100 cubic feet. As the utility or provider. If there was no leak for years prior but there is now and suddenly there is a documented unexplained increase in fuel then look to what has changed. If the only change is them changing cylinders then they obviously damaged it. Also, when they swap cylinders, they should treat it as a new install and inspect the lines then perform leak checks. If the kink didn't leak at the time of swapout, then inspect the stability of the cylinders and fuel line. Tim, do you have a reference for requiring coated copper tubing on high pressure lines? I do not see this in the code but only the acceptance of ASTM B-88 types K or L or ASTM B-280 AC/R. Compression fittings not approved per IRC G2414.10--use flares. CSST is allowed for the low pressure lines downstream from the second stage regulator when installed per the listing. Always check with local building dept. for local ordinances, requirements and inspections in addition to the building and fire codes.

summer CO

@ June 25, 2012 4:25 PM in CO deaths in Portsmouth, VA.(Norfolk area)

I think someone qualified needs to inspect all the venting then conduct combustion analysis with depressurization testing to see if it was a combination of hot weather when there is no appreciable natural draft at standby coupled with leaky return ducts depressurizign the CAZs or some similar mechanism to entrain CO. Of course, they would have to rule out exogenous sources of CO such as idling cars, BBQs, pool heaters, and groundskeeping gasoline powered engines.

Jim have you tried contacting the Fire Marshal's office? You ought to. UL listed alarms don't even make decent paperweights.

response to high CO

@ June 2, 2012 7:16 PM in Awareness: A little tidbit #4

Tag out/ lock out offending appliance. Homeowner should sign your paperwork noting appliance is 'dangerous' as defined by ANSI stds. To re-connect the appliance and operate it as is presents an immediate threat to life safety and/or fire. Recommend the unit be repaired or replaced with one that can operate within the mfrs. specs and industry stds. Also recommend an unlisted low level CO monitor.
The appliance's gas line should be disconnected and capped and the operating control disabled such that both require tools to place it back into operation.

different sensor technology

@ June 1, 2012 7:51 PM in CO Safety Switch?

Depending upon the sensor type and quality can vary its service life for years. Yes, 5 is the max. recommendation on UL listed alarms. The oxygen in the air degrades the sensor over time.That's why even unsold alarms have a limited shelf life. Very high levels of CO and NOx can adversely affect sensors, too.

One thing you have to keep in mind is the time function. Are you going to send the calvalry for a whiff of CO? That's specifically why they dummied listed alarms down to reduce false positives and the number of alerts. They'd rather not come out unless you're almost dead Doesn't respond to chronic low levels.
If the sensor got covered with soot, it would nullify it. The face of the sensor would have to be not only super corrosion resistant but meet the rating of the chimney/ vent and not cause turbulence or reduce the flue capacity. It would have to be written into the listing standard such as ANSI Z21.47 and listed as part of the entire appliance. A lot of problems doing this.

unqualified first responders

@ June 1, 2012 12:22 AM in Carbon Monoxide: A Step Backwards

The fire depts, utilities, fire marshals and other first responders are wholly unqualified to respond to CO-related calls. Also, the incident reporting forms and mechanisms are a joke so the actual numbers of exposure are MUCH higher than being reported.

CO switch technology

@ June 1, 2012 12:17 AM in CO Safety Switch?

To hardwire a UL listed CO alarm onto a combustion appliance is a little fruitless based upon current technology and the UL listings 2034 & 2075. These alarms will sound only once you already have a 10% COHb level and even then they are unreliable. We have relatively reliable temperature based spill switches when mounted where they will be most effective. However, where would you mount a CO switch on let's say your typical draft hood equipped gas boiler? The draft hood? Where? Flue gases are notorious for spilling out one side of draft hoods. What if the HX is plugged and its venting out of the base? What if the chimney draft is so excessive it creates a door curtain effect blocking venting at the draft hood? What if there is a shunt inside a forced air cabinet between the combustion chamber and the return air plenum? Where do you place it on CAT III & IV forced draft units? One at each joint in the venting? You see the dilemma?
A better solution would be to require performance testing by technicians who are certified and trained in combustion analysis and CO. Positive pressure venting should be tested for integrity but we on the UL Standards Technical Panel cannot agree on this need, much less a standard. We still are working on the listing for polymer venting. CO switches on combustion appliances is actually a very complex issue. Meanwhile, if you want to offer real protection for your clients, install unlisted CO monitors in addition to the code required listed junk.
HTH

UL listings

@ May 26, 2012 10:50 PM in Carbon Monoxide: A Step Backwards

A typical listing costs about $15K plus paying for the 4 quarterly unannounced plant inspections per year.
The UL 2034/ 2075 listings allow for chronic low level CO poisoning. Worse yet, if your listed CO alarm sounds, that guarantees you already have CO poisoning. Those alarms are set to sound based upon a carboxyhemoglobin level of at least 10%. Gee thanks for nothing.
Listed CO alarms are known to be very unreliable still.
At their lowest response level, you can be exposed to 70ppm for up to 4 hours before the alarm sounds or 69ppm for 30 days. Gee thanks. They deliberately dummied the alarms to reduce calls for non-life threatening situations. Gee thanks.

RRP

@ May 22, 2012 4:15 PM in stripping (blasting?) and repainting radiators

Don't forget your RRP obligations. I would have a paper trail making him also responsible for compliance in his methods of handling and preparation. You are probably responsible for testing painted rads before you remove and handle them then disclose those test results to him.
Any form of paint or coating will act as insulation and reduce the effectiveness of a rad. Consider using a flat black matte finish where possible. Also, radiator covers are a bit of an oxymoron.

CO alarms

@ May 20, 2012 10:00 AM in Carbon Monoxide: A Step Backwards

Pennsylvania is set to adopt their version of mandatory UL listed CO alarms. The bill is sitting in appropriations but will pass. It requires annual inspection by.................home inspectors! In addition, rental units will be required to be inspected when tenants leave. I tried to get heard but was shut out.
There is legislation floating out there in Congress attempting to outlaw unlisted CO 'alarms'. This is a stinky move by the big alarm mfrs. in bed with the fire marshals and fire depts. Colllectively, they want to sell a bunch of cheap POS units so they can rest on their laurels as being caring and responsible. This also ensures less CO responses for those fire depts already understaffed.
To me one of the key shortcomings of a UL listed CO alarm is the premise that in order for it to sound, it waits until you have approximately 10% CoHb then supposedly alerts just in time to wake you and save your life. This means in order for it to work, you already must have CO poisoning! Gee, thanks...BTW, you're looking at CO poisoning for at least 4hrs on the low end. This is nuts! This doesn't even address the reliability issue which has been and still is a problem with UL listed junk.
The mortality and morbidity rates are grossly inaccurate because of the lack of a reliable, accurate reporting system. We know the true exposure rates are far higher and will get much worse as time goes on.

preventative medicine

@ May 6, 2012 9:51 AM in What they do in England

When I am finished with either inspecting an installation or working on one, I always run my hands around every pipe joint to count the screws and feel for how intact the pipe and joints are. I grasp the pipe and giggle it to ensure it is properly connected and supported. I do a lot of inspecting work and have screwed loose pipes on hundreds of installations at no charge simply because it was the right thing to do. It is sad how rampant it is that supposedly 'professionals' are willing to pack their tools and walk off a job leaving the occupants with disconnected pipes, unsecured pipes or never looked into the chimney AS REQUIRED BY CODE to see if it was blocked, collapsed or otherwise unsuitable. Everyone focuses on the things that won't kill you and neglect the one thing that will--improper venting.

insurance

@ March 6, 2012 8:16 AM in Is this vent pipe installed incorrectly and the source of my problems?

Call your insurance carrier. You'd be surprised at what they will cover. You could contact a PA and have them go to bat for you.
I suggest you read up at buildingscience.com  Dr. Joe Lstiburek has a lot of free download articles on the subject and you'll be shocked at this views on attic ventilation.
You could hire a contractor who is BPI certified who can conduct a blower door test with  infrared thermography, which will show you the extent of the moisture intrusion and any air bypasses. For sampling, you'd need an industrial hygienist and they ain't cheap, which is why I suggested the insurance route.
You have multiple issues here and probably multiple sources of moisture. For instance, that fart fan with the plastic slinky vent may have become torn or disconnected and could discharge/ leak moisture into the attic or its discharge may not be making it outside. The exhaust fan probably is not sealed to the bathroom ceiling allowing moisture migration around it. Those boxes leak like a sieve on a good day anyway. A lot of that moisture appears to be coming up from the roof deck/ flashing. You can have your pvc vent tested by a plumber with inflatable test balls to see if the joints are intact but I doubt it is discharging sufficient moisture to get entrained back into the attic.
HTH

chimney venting

@ February 14, 2012 10:18 AM in Chimney liner sizing problem

All chimneys must be suitable for the class of service. All chimneys must be lined. Therefore, your original setup was non-code compliant. According to the sizing tables in the gas codes, the 10x10 was undersized for this load.
Since you cannot common vent both appliances into this chimney, you have two options:
Power vent or get rid of the water heater and replace it with an indirect tank. I would opt for the second with a single properly sized listed liner. To power vent, you have two methods: push it out or suck it out. Sucking it out with the fan on the building's exterior allows you to use conventional vent connector and a listed liner. Yes, you would still need the liner. If the fan was at the appliance, the venting must be listed for positive vent pressure, meaning listed to UL 1738. This is the AL29-4c stainless steel with gaskets. You have to verify your termination meets all the code requirements and is not below snow level. Either type of fan will require a pressure proving switch of some sort. I recommend you have a pro perform a level II inspection of the chimney to ascertain its suitability even if relined before going farther. HTH,

sudden occurrenece loss

@ February 13, 2012 9:10 AM in Failed Furnace installer blames propane supply

This is waaaay out of hand here. This is a "sudden occurrence loss", which means it should have been turned over to the homeowner's insurance company on day one. They would hire another HVAC contractor to replace the venting and unit then, with the assistance of the investigating engineering firm, take the old unit into custody. The interested parties would all have to be identified and notified as quickly as possible so they could have a representative present at the Tear Out/ Re-Install and securing of the old unit and pipe. The homeowner gets heat back on same day with an entirely new unit.
The engineering firm conducts their investigation into the cause and origin and reports to the insurance carrier who, in turn, subrogates to the likely suspect. They negotiate a settlement-done.
Now, part of your problem does sound like an issue with inadequate fuel delivery. The problem manifested during a cold spell with two probably undersized tanks.This refers to the 'vaporization rate' of those tanks. As it gets colder and the liquid phase fuel level drops, those tanks become unable to vaporize fuel fast enough for he load. Two undersized vertical DOT cylinders were recently refueled waay too quickly. This should have been a red flag. Each 100lb cylinder holds roughly 2million BTUs available. That's a lot. So, unless all the upstairs windows were left open, you need to look at the firing rate of the unit and correlate the temps over that period to see if the fuel consumed correlates to the fuel it should have required.
I highly recommend using buried ASME containers in northern climates. Also, were is the medium pressure regulator? Is it at the tanks or close to the appliance? What is the diameter and run of the low pressure gas line from the MP reg to the appliance. Any other loads? Any kinks?
You can clock an LP system with a standard NG meter then multiply the result by a factor provided by the meter mfr., usually around 0.63
If someone removed the orifices that were in place during the incident, this constitutes a 'spoliation' of evidence. This means you lose your arguement to defend yourself by masking the evidence. Anytime there is an incident, you must play fair and allow all the interested parties and equal chance to inspect  the evidence. Tampering and spoliation can result in shooting yourself in the foot.
If those PVC pipes saw high temps, you could have pyrolysis of nearby combustibles such as any holes bored the pipes pass through. This case needs professional investigation.

leaks

@ January 26, 2012 7:50 AM in LP gas valve

Gas cocks are rate either 3 or 5 psi depending upon mfr. However, you NEVER test at pressures over 14 wci past a gas cock with an appliance connected. Gas combination valves are allowed trace gas leakage by ANSI of 200cc/hr through the seals of the valve and 235cc/hr through the main operator leaking to the burner both at 3/4psi or 21 wci. You can check to see if gas is still leaking out of the main operator or the regulator vent when the burner is shut off and you're leak testing. Has anyone tested the vent on the second stage regulator to see if it is 'leaking' constantly. If so, you have a blown diaphragm. Note that lower pressure leak tests are more accurate than high pressure tests.A water manometer or bubble meter is what is used in the lab. Also check your hoses and connections on your manometer. Use a commercial soap soln. such as Big Blu with know characteristics and give it time.

VF field conversions?

@ January 18, 2012 8:19 PM in from propane to natural gas?

Ventfree gas appliances are NOT field convertible. That would void the warranty and listing. You must order a separate appliance set up by the factory for the alternative fuel.
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